Printed circuit assemblies are used for numerous electronic applications these days. The printed circuit assemblies contain a number of interconnections, wirings, through vias and plated through holes extending from external connections on one surface of the printed circuit assembly to wirings and connections on the opposite surface.
Often the printed circuit assemblies—because of incorrect design or manufacturing errors—end up carrying defects. The defects in the printed circuit assemblies may include undesirable short circuits, open circuits or misrouted traces. Even a single defect in one of a plurality of connections on the printed circuit assemblies can lead to the entire assembly being deemed defective. The defect in the connection and associated through vias must be either repaired or completely replaced else the defective printed circuit assemblies will have to be discarded.
There are a few known solutions for repairing of defective printed circuit assemblies. One solution being deep deletion of the defective through via. The deleted through via is then filled with an epoxy solution and then a new through via is drilled and the connections are soldered again.
The problem with such a solution is that additional wires need to be added to the printed circuit assembly. Also, since the printed circuit assembly has a plurality of interconnections; it becomes difficult to solder new interconnections in such a tight package of the plurality of interconnections. Such soldering may also lead to short circuits and some other additional defects in the printed circuit assemblies.
Also, in cases of Land Grid Array (LGA) applications, multiple interposers are used in a stacked structure to repair a defective LGA. The stacked structure may lead to overcrowding of interconnections in the LGA and may lead to short circuits within the LGA.
Therefore, in light of above discussion there is a need of a solution that facilitates easy and safe rework of defective printed circuit assemblies.